Contents

Methyl cation, anion, and radical

Methyl cation

The methylium cation (CH3+) exists in the gas phase, but is otherwise not encountered. Some compounds are considered to be sources of "CH3+," and this simplification is used pervasively in organic chemistry. For example, protonation of methanol gives a strongly electrophilic methylating reagent:

Methyl anion

The methanide anion (CH3-) similarly exists only under exotic conditions. In discussing mechanisms of organic reactions, it is often a useful simplification to consider methyl lithium and related Grignard reagents as sal sources of "CH3-," although this view is fiction. Such reagents are generally prepared from the methyl halides:

where M is alkali metal.

Methyl radical

The methyl radical has the formula CH3. It exists in dilute gases, but in more concentrated form it readily dimerizes to ethane. It can be produced by thermal decomposition of only certain compounds, especially those with an -N=N- linkage.